Method of making woven wire belts



Aug. 11, 1942. v w. c. SUTTON METHOD OF MAKING WOVEN WIRE BELTS Original Filed Sep't. 21, 1939 3 Sheets -Sheet l INVENTOR.

ATTORNEYS Au 11, 1942. w, c, SUTTON 2,292,412

METHOD OF MAKING WOVEN WIRE BELTS Original Filed Sept. 21, 1939 3 Sheets-Sheet 2 IN VENTOR.

ATTORNEYS Aug. 11, 1942. w. c. SUTTON METHOD OF MAKING WOVEN WIRE] BELTS Originaliiled Sept. 21, 1939 3 Sheets-Sheet 3 INVENIOR 7M1! Cwurzm ATTORNEYS.

v IIIIIIZNMM \k r by/ll!!! A K @W \W W mw n 3 G Patented Aug. 11, 1942 OFFICE 2,292,412 METHOD OF BEAKING; WOVEN WIRE BELTS Walter C. Sutton, Shaker Heights, Ohio, assignor to The Lindsay Wire Weaving Company, Cleveland, Ohio, a corporation of Ohio (01. IMF-3) 12 Claims.

This invention relates to a method of manufacturing woven wire belts, especially to such belts as are useful in Fourdrinier machines.

The present application is a division of my copending application which became Patent No. 2,221,696 issued November 12, 1940, and which is now restricted to an apparatus and which claims the apparatus which is herein shown to illustrate the method.

Woven wire fabric when used as a belt in paper-making machines is rapidly and repeatedly bent in opposite directions as it passes over the various rolls and suction boxes of the machine. Such reverse bending imparts stresses to the fabric which are so severe that the life of a belt which is made in the customary manner of weaving, averages only about thirty days.

Firmness is an essential quality in a Fourdrinier wire belt. Sleaziness or looseness of the fabric tends to cause wrinkling and shorter operating life. Twill weave fabric, while somewhat more susceptible to sleaziness than the older plain weave wire cloth, has other advantages, as outlined below, which make it valuable for many machines,

One of the advantages of twill weave over plain weave is the fact that more wearing surface is available on that side of the belt which is subject to the abrasive action of the suction boxes. In twill weave, each warp wire passes over one weft wire, and under two weft wires in succession, but so far as I am aware, no one has been able to so weave a twill fabric that the underlying portion of the warp wires extend parallel to the plane of the top surface on the suction boxes; instead, the under portion of each warp wire has extended at an angle to the surface of the suction box and consequently has formed a knuckle which takes the initial wear. The area of the knuckle so formed is considerably smaller than the area of the entire underlying portion of each warp wire and hence the wear is concentrated, and the warp wires have been worn through prematurely.

The disadvantage of the twill weave, however, is the fact that a paper web formed on the twill is marked more than that formed on a plain weave, because the weft knuckles are more widely spaced and do not rise to the plane of the top of the warp knuckles in the normal weaving operation; but the co-planar relationship of the warp and weft knuckles has been improved by beating up the weft wires to a greater degree. Such actien has increased the pressure against the warp wires, accentuating the angularity of the underlying portions of the Warp wires, so that a gain in smoothness on the top surface of the belt has been commensurate with a loss in available wearing surface from the bottom of the belt.

An object of my invention is to make a wire fabric which is firmer and more compact than that obtained merely from a weaving operation, and which will therefore possess greater mechanical strength and resistance to fracture from successive bending in reverse directions.

An additional object is to make a fabric which, when woven as a twill weave, will have the top of its warp and weft knuckles in the same plane and will have the underlying portions of the warp wires disposed for substantially their entire length parallel to the plane in which the topmost surfaces of the belt lie, and therefore parallel to the plane of the wearing surface of the suction boxes.

Flattening or leveling of the cloth as a whole improves its performance on both the upper and under-surfaces, as it makes a more level support for the paper, and less abrasion of the suction boxes. To effect such leveling, it has been proposed to submit the woven fabric to pressure between rotating rolls which have been supported at their ends in journal boxes pressed toward the fabric. So far as I am aware, this method has not been successful for wide belts, because no alteration in the position of the wires in the fabric could be obtained without the application of a comparatively heavy pressure, and when adequate pressure was applied, the rolls which would necessarily be quite long, since belts may be as much as 25 feet wide, would deflect in the intermediate region and thus only press the fabric sufficiently to flatten it in the region of its margins, without altering the formation in the central region. The permissible flattening is only a few thousandths of an inch, and it has been found that a deflection of the roll greater than about a thousandth of an inch renders the operation useless.

It has also been proposed to roll the wire cloth transversely, a narrow strip at a time, before the ends are joined. This method has introduced unevenness in the junction of the rolled zones and has interfered with the proper formation of the seam when the ends are joined into a belt, and has other disadvantages, so that it has never come into common use.

The present invention provides means for flattening wire cloth of any width, using equipment already available with the additional parts; requires only moderate power for its operation, and

provides absolutely uniform pressure, flattening the fabric across the entire web with moderate flattening of the individual wires. The cloth is rolled after seaming as an endless belt, and the disadvantages of former attempted methods are overcome.

This feature of the present invention may therefore be characterized as providing a method for treating woven wire fabric so as to accomplish the desired leveling without damaging the fabric or interfering with its utility.

The method of this invention is illustrated in the accompanying drawings, which show'an apparatus for carrying out the method. In these drawings, Fig. 1 is a top plan view of an apparatus embodying my invention; Fig. 2 is a section on the line 2-2 in Fig. 1; Fig. 3 is a section on an enlarged scale through the fabric on a plane parallel to the Warp wires, showing the relation of the warp and weft knuckles before the fabric is treated in accordance with the method of the present invention; Fig. 4 is a similar vertical section illustrating the fabric of Fig. 3, after it has been treated in accordance with the method of the present invention; Fig. 5 is a vertical section on an enlarged scale taken on the line 55 in Fig. 1; Fig. 6 is a horizontal section taken on the line 62-45 in Fig. 5; Fig. 7 is an horizontal section taken substantially on the plane indicated by the line 1-7 in Fig. 5; Fig. 8 is a vertical section as indicated by the line 88 on Fig. 6, but on a larger scale, and with the cover plate removed.

In Figs. 1 and 2 of the drawings, A indicates a woven wire fabric joined by a seam into an endless belt, the fabric being in the condition it comes from the loom. This condition may be such as is indicated in Fig. 3, where B designates one of the warp wires and C the weft wires in a twill weave. It will be seen that these weft wires are respectively below the top plane and above the bottom plane tangent to the warp knuckles; Fig. 4 illustrates the same fabric after it has been treated by my method about to be described, to flatten it, so that the topmost and bottommost regions of the weft wires C! are respectively in the same plane as the topand bottom of the knuckles of the warp wires Bl.

In Figs. 1 and 2 I have illustrated a usual belt stretching table, the stretching apparatus comprising two large rolls IE and 2&3, adjustably spaced so that the belt may pass around them and be maintained taut. As shown, the roll Iii has journal boxes H mounted in a movable carriage [2. This carriage is shown as having rollers i3 resting on parallel tracks I5. These carriages are manually positioned and held in various locations by struts It engaging periodicallylocated recesses H in the tracks. This provides a rough adjustment for belts of different length.

The roll 20 has its bearing boxes 2| mounted in carriages 22 which are slidable along the trackways 15 for a short distance. Devices, herein after described, are provided for moving and holding these carriages 22 to tension the belt.

The fabric may be joined into a belt by a suitable seam either before or after it has been passed about the rolls, as desired. If the seam is formed before mounting the belt on the rolls, the rolls (which have their bearing boxes removably mounted in the carriages l2 and 22) are raised from the carriages and supported by any suitable mechanism, while the belt is passing over the rolls endwise thereof.

Means are provided for rotating the roll 26, for instance, in a motor 30, driving reduction gearing 3i and 32, to a final shaft 33, which aligns with and is coupled to a gudgeon extending from the roll. The motor with its reduction gearing is mounted on a platform and is capable of sliding'movement parallel with the trackway [5, corresponding to the shifting movement of the roll 26.

Extending across the apparatus on the outer side of the roll 29, and parallel with it, is a stiff horizontal beam 4! shown as an I-beam, with its web in a horizontal plane. This beam may rest near its ends on ledges 28 on an extension 29 of the standards 22. The I-beam 40 is adjusted toward the roll 23 by a pair of jack screws 42 (Fig. l) threaded in ears carried by the bracket extension 29.

The adjustment of the roll 28, heretofore mentioned, is effected by rotatable screws 59, mounted in fixed brackets 5|, threadingly engaging extensions 52 of the carriage 22.

To operate the two screws SE! in unison, l couple each of them with an aligned shaft 53, which is connected by bevel or worm gearing in a housing 54 to a transverse shaft'55. This shaft 55 is driven in one direction or the other, as may be desired, by a motor 56, controlled by a reversing switch 51, and operating reduction gearing which is connected to the shaft by a sprocket chain. Automatic operation of the motor to maintain tension on the belt will be described later.

The I-beam Ml carries on its vertical face, adjacent the roll 23, a rotatable roll of small diameter engaging the web and pressing against it throughout its width to flatten the web as it travels by the rotation of the roll 20, which acts as the resistor to the pressure. This device will now be described, with reference to Figs. 2', 6 and 8.

The pressing roll, above referredto, designated 6t, is a cylindrical rod, which extends horizontally in the plane of the axis of the roll 20, for the full width of the maximum belt; which may be carried. This rod is movably carried in a horizontal slot in the front face of a long, closed housing 6|, secured to the vertical face of the I- beam 49, as shown in Figs. 2 and 5. The housing 6| may, for the most part, be a casting. This casting is suitably secured to the I-beam 49, yet

has top and bottom walls which carry at the front a pair of spaced plates 68' (Fig. 8) which extend the full length of the housing, and carry on their outer faces leather plates 1E] which ex tend downward and upward respectively into en gagement with the roll 60. These leather plates are clamped in place by metal plates 12 suitably secured to the housing.

The plates l2 are separated by a distance less than the diameter of the roll 60, so that they form a limit for the movement of that roll to-- ward the roll 23, such outer limit being indicated by the broken line Efi--a, in Fig. 8, an operating position of the roll Eli being there shown in full lines.

Above and below the roll 66, long non-abrasive material strips 15 fit into rabbeted edges in the plates 72 and form top and bottom bearings for the roll. These strips 75, as illustrated in Fig. 8, have recesses in their rear portions occupied by long elastic rods l8, preferably of rubber, each of which carries a plate Ti bearing against roll 66 and supporting the free edge of the leather packing plate 10.

The construction described makes an air-tight connection with the inner portion of the roll 68,

while that roll is free to move a short distance toward the roll 20. Compressed air supplied to the housing BI (which is effectively closed at its end portions, as hereinafter explained) forces the rod 60 outwardly against the web with considerable pressure, so that the roll 60 rolls in cooperation with the roll 20 and flattens the web as it travels.

Within the housing 6| are two rotatable screws 80, journalled at their inner ends in bearing blocks 8I, within the housing (Fig. 6) and extending at their outer portions through the ends 69 of the housing. These screws extend threadingly through blocks 84 in the housing. These blocks carry packing which makes an air-tight connection with the roll 60. Compressed air is admitted through an opening 85 into the space within the housing between the two blocks 84, and thus acts to press that portion of the roll 69 which is between these blocks against the belt.

Rotation of the screws 80 moves the blocks 84 inwardly or outwardly, so that they may be adjusted to bring their packing in line with the marginal edges of the belt, so that the com.- pressed air is acting on that portion of the roll 60 which extends entirely across the belt, but not on the idle end portions of the roller, if the belt has less than the maximum width.

The means by which I obtain an eflicient packing between the blocks 84 and the roll 60 is illustrated in Figs. 6 and 8. Mounted in a recess 93 in each block 84 are a number of parallel plates 9I, side by side, pivotally mounted on a cross-rod 92. Each plate has a narrow inward extension 93, and these are interleaved with thin plates 94 carried by the block. The inward extensions of the plates 9i are of different length, so that the outside edges of the set present a concave contour, as shown in Fig. 8, which, in the intermediate region, corresponds to an arc of the roll 60. A thin flexible plate 95 lies across the ends of the plates 9|. The projecting portions of this plate, above and below the roll 69, bear against the free portions of the leather backing "I0, heretofore mentioned.

The plates 9I have their free end portions 96 bevelled on their inner edges, and this bevel is engaged by a suitable leather packing Hi leading from a leather hub IBI threaded on the screw shaft 80. This packing I09 engages the walls of r the housing and is held in place by a metal plate I65, held to the block 84 by screws I08. This plate is formed, as shown in Fig. 8, slitted adjacent the rod 60 to provide spring tongues Illt pressing on the leather packing I60, and causing the latter to cam the plates 9| outwardly to exert pressure on the packing strips ll). The plate I G also is slitted about an opening which surrounds the screw shaft 80, providing radial tongues IIli pressing against the hub packing above the screw shaft.

It results from the construction described that an airtight adjustable end member is provided for each end of the air chamber within the housing 6 I The leather packing Ill, heretofore mentioned, makes an air-tight connection aboveand below, with the roll 60 throughout the length of the .roll so that that packing is active for the distance between the blocks 84. Accordingly, a closed air chamber is provided between the blocks 84 which maintain compressed air under comparatively heavy pressure, thus forcing the roll 60 against the web with sufficient force to flatten it from the form. shown in Fig. 3 to the form shown in Fig. 4, as the web travels. In this manner, I

am able to maintain the small roll 60 in uniform and effective pressure against the web, and thus flatten the web uniformly throughout its width.

As the position of the blocks 84 is hidden from direct observation, I employ the following external mechanism for indicating such position to the operator. Extending across the apparatus directly above the housing BI are a pair of aligned horizontal screws III] and III, Figs. 1 and 7. These screws at their outer ends have sprocket wheels II2, while sprocket chains II3 (Fig. 5) extend around these wheels and around corresponding sprocket wheels II4 on the ends of the screw shafts Bil. Threaded on the screws I II] and II I are indicating fingers I I5, which are slidably guided by the vertical flange IIG of the I-beam M3. The fingers II5 are located in correspondence with the active edge of the packing on the blocks 84, and hence if the screws are rotated such movement automatically moves the blocks 34 and the fingers II 5 so that they indicate the new position of the blocks. These screws I I0 and III thus serve the double purpose of actually moving the blocks 84 to change their position, and of indicating such changed position.

The means for driving the screws IIO, III, to move the blocks 84 and their indicators, comprises a hand belt I located in a convenient position for manual engagement by the operator. This hand belt extends over an idle pulley HI, and over a driving pulley I22 on a shaft I23, the latter shaft operating the screws, as about to be described.

Referring to Fig 7, it will be seen that the shaft I23 is mounted in a bearing I24, carried by the I-beam 4i), and has on its inner end a bevel gear I25. This bevel gear meshes with a bevel pinion I2 3 tight on the shaft Ill], and a bevel pinion I2'I loose on the shaft III. An intermediate slidable sleeve ISO is splined to the shaft I I I, and this sleeve has clutch teeth at its opposite ends adapted to mesh with teeth on the ends of the hub of the pinion I26 or I2'I, as th case may be. The sleeve I30 may be shifted by a suitable manual lever I3I.

With the parts in the position shown in Fig. 7, when the shaft I23 i rotated, it drives the screw shaft IIO through the fixed pinion I26 in one direction, and drives the loose pinion I21 in the other direction. The loose pinion being connected by the clutch with the shaft III, rotates the shaft in the opposite direction to the shaft I I0.

It follows that with the clutch I30 in the position shown in Fig, 7, the rotation of the shaft I23 by the shifting of the hand belt I28, in one direction or the other, carries the two blocks 84 and the two pointers H5, toward or away from each as the case may be. This enables the spacing of the blocks and pointers corresponding to the width of the web.

When it is desired to cause the two blocks and their two pointers to move as a set toward the right or left, to accommodate belts of the selected width, but differently positioned on the rolls, the clutch lever I3I is thrown to the left (in Fig. 7) thereby clutching the sleeve I30 to the hub of the pinion I26, which is fixed on the shaft lit and then that pinion drives both shafts Ill] and III as a unit. As the threading on thes shafts is in the same direction, this operation will shift the blocks and fingers to right or left while preserving their spacing.

Accordingly, when the clutch lever I3I is in one position, the operation of the hand belt I accomrnodates the blocks and pointers to the position of the belt on the roll 28; whereas, when the clutch lever is in the other position, the blocks and fingers are caused to approach or separate to accommodat belts of different widths, as heretofore explained.

I have heretofore referred to the motor 56, Fig. 1, as operable when desired to shift the position of the roll 29. This motor is also employed to maintain the constant tension on the belt during operation. In effecting this, I may employ a suitable automatic hydraulic drive unit 59, acting according to the torque on the transverse shaft 55, which will energize the drive when the torque decreases to a predetermined amount. Accordingly, the drive unit operates to move the roll toward the right, thereb stretching the belt until the tension on the belt increases the torque load to the predetermined maximum which stops or slows the drive unit. taining the belt in a constant tension, though the flattening action on th web, a hereinafter described, tends to slacken the belt. Such slackening is taken up by a slight outward shifting of the roll 2%, the roll 65 and its supporting I-beam 48 being carried with it.

The compressed air may be supplied to the housin 6| by any suitable means. In Fig; 1 I have illustrated at Mil a motor-driven compressor supplying air by a line MI and through a regulator M2 to the port 85 in the housing. I have found that with a roll fiB having a diameter of air pressure of between 200 and 250 lbs. per squar inch operates very satisfactorily on phosphor bronze fabrics having an original thickness of about .62 inch. The air pressure, however, will vary according to the eharacteristics of th fabric to be flattened.

It will be seen that by reason of the roll 60 being somewhat flexible and pressed by substantially uniform pressure throughout its effective length against the resisting roll, any flexing of the resisting roll due to the pressure is immaterial, as that simply results in th roll 6i! being pressed correspondingly further forward so that the fabric is rolled to a uniform thickness across the web.

By employing a roll of smaller diameter,-I have found the diameter of satisfactory not only can I make the engaging line of that roll stand strictly parallel with the engaging line of the resisting roll, but I obtain a more effective pressure on the wire, as such pressure is confined at any one time in a very narrow zone across the web, and hence more force acts at f on time on each cross-sectional plane of the wires engaged than if the roll were larger and its region of osculation extended for a greater distanc along the wires, particularly the warp wires.

In operation after the belt has been installed, the tension applied, the air supplied to thepressing roll, and power connected for rotating the driving roll of the stretching frame, the operation is automatic. The amount of air pressure, as well as the amount of tension, and the number of passes of the fabric through the pressing device, varies considerably with different thickness of the belt and different material employed.

I have found that with belts of phosphorbronze wire, of some sizes and meshes commonly used by paper mills, a tension of about 20 lbs. per inch of width of the belt, and an air pressure of about 200 lbs. per square inch, is very satisfactory.

It is preferable for the cloth to make two or This provides for mainmore successive passes under the pressure roll. In fact, the pressing operation may continue until each region of the belt has travelled a number of times past the pressing roll, which gradually compresses the web uniformly across the belt until the resultant web has a uniform thickness and all of the knuckles come to the bounding top and bottom planes.

I have found that in order to secure the maximum firmness in the cloth after rolling, it is desirable to pass it through the rolls in the direction opposite to that in which it was woven. This forces the weft wires against the steeper end of the warp crimps and locks the two firmly together.

By. using the small roll effectively pressed against the web, and truly parallel therewith, and applying uniform pressure against the progressing web, the web is gradually flattened to stretch as it travels. The stretching which is incident to the use of the method is apparent in Figs. 3 and 4, where the distance between the lines D and E represents the spacing between six weft wires before treatment, and where the distance between lines D and F represents the space between the same weft wires after treatment.

While I have described my invention particularly as applied to. the manufacture of woven wire fabric, it is to be understood that the method may be desired to be utilized for treatment material other. than wire fabric, such as sheet-metal, papenfibrous materials, or any other material which is reduced in thickness by its passage between two rolls.

I claim:

1. The method of making a woven wire belt for use in a paper-making machine, comprising weaving. a web of fabric and joining the ends of the web to form an endlessbelt and then pressing the belt and seam to reduce the thickness and bring the knuckles and seam to a common plane.

2. The method of making a wire belt for a paper-making machine, comprising weaving a wire cloth and joining the ends thereof by a transverse seam and thereafter pressing the cloth and seam between rolls under pressure distributed substantially uniformly along the regions of the rolls which engage the belt and while moving the belt longitudinally.

3. In the method of forming a woven Wire belt for a paper-making machine, the step of passing the woven fabric between rolls extending entirely across the belt at least one of which rolls is somewhat flexible and pressed intermediate of its length toward the other roll.

4. The method of making a woven wire belt for a paper-making machine, comprising weaving it with a twill weave and thereafter submitting it to pressure applied in the direction of the long knuckles of the warp wires.

5. The method of making woven wire fabric for a paper-making machine, comprising weaving the fabric and thereafter submitting it to pressure successively along a Very narrow zone extending crosswise of the web while, supporting it on the. opposite side in a much Wider zone, the pressure being submitted uniformly throughout the entire zone, and simultaneously moving the web in a direction parallel to the length of its warp wires.

6. The method of making a woven wire belt for a paper-making machine, comprising weaving the fabric, joining the ends thereof to make a belt, pressing the belt successively by pressure distributed uniformly entirely across the width of the belt and extending longitudinally for a very short distance at any one time, and moving the belt relative to the pressing means in the direction of the length of the warp wires.

7. The method of making a Woven wire belt for a paper-making machine, comprising weaving a web, joining the ends thereof to make a belt, stretching such belt on the two parallel rolls of a stretching machine, and leveling and flattening the wire cloth while it is running on such rolls by pressure acting simultaneously in the direction of the weft wires and successively in the direction of the warp wires.

8. In the method of making a Woven wire belt for a paper-making machine, the step of stretching a wire cloth in an endless belt under controlled tension in the direction of the length of the warp wires and compressing the belt in thickness while it is being stretched.

9. The method of making a woven wire belt for a paper-making machine, comprising weaving it with a twill weave and submitting it to pressure between rolls extending transversely of the web, at least one of said rolls being of comparatively small diameter and the rolls being maintained with their lines of coaction substantially parallel, and means for rotating said rolls to cause the belt between them to move continuously in the direction of the length of the warp wires, whereby the web is leveled and flattened uniformly.

10. The method of leveling and flattening wire cloth comprising passing it lengthwise of the warp wires between rolls transversely extending and pressed toward each other, the direction of movement of the cloth being such that the pressure of the rolls forces the weft wires in the direction in which they were beaten while weaving.

11. In the method of making a Woven wire belt for a paper making machine, the steps of weaving a web, joining the ends thereof to make a belt, leveling and flattening the web without removing material therefrom by passing it between rolls extending transversely of the length of the web and at the same time maintaining the belt under substantially constant tension in the direction of the length of the warp wires.

12. The method of forming a woven wire web for use in a paper-making machine, comprising weaving a wire fabric, thereafter submitting it to rolling pressure by means which on one side has a comparatively wide zone of contact with the web and the other side has a comparatively narrow zone of contact therewith, measured in the direction of the length of the warp wires, said zones extending in length across the warp wires, thereby compressing the web in the direction of its thickness and slightly lengthening it, and during such compression maintaining the web under tension and progressing the belt relative to the pressure produced uninterruptedly lengthwise of the warp wires.

WALTER C. SUTTON. 

